Previous studies have identified genes linked to strokes caused by reduced blood flow to the brain, and bleeding.

Lead scientist Professor Sudha Seshadri, from Boston University Medical Center in the US, said: "Unravelling the mechanisms of small vessel disease is essential for the development of therapeutic and preventive strategies for this major cause of stroke."

The research highlights a novel biological pathway affecting pericytes, a type of cell in the walls of small arteries and capillaries.

Small blood vessel disease in the brain is also a major contributor to dementia risk and is associated with gait problems and depression, the scientists said.